The present invention relates to a method for identifying the concentration of fuels or gases in air. More particularly, the present invention relates to a method for identifying the concentration of fuels or gases in the intake air of motor vehicle motors with ultrasound measurements. Further, the present invention relates to an apparatus for identifying the concentration of fuels or gases in air.
Motor vehicle fuel tanks have been recently equipped with activated carbon filters that bond fuel vapors. The carbon filters prevent the vapors from escaping into the atmosphere. In the regeneration of the filters, the fuel vapors bonded to the filters are transported into the intake air of the motor and are subsequently burned in the motor.
For an optimum pilot control of a given air/fuel ratio, the proportion of fuel supplied to the intake air from the activated carbon filter must be taken into consideration. A sensor for the concentration of the fuel vapor in the intake air would be expedient for this purpose. Prior proposals or attempted solutions for identifying the air/fuel ratio are based on what are referred to as chemosensors.